IONOS: Changes to email sending since January 2024. What do I have to do?

What changes have been introduced to IONOS?

In order to increase the security of IONOS customers, emails will be sent via their email server with alternative or empty sender addresses from January 29, 2024 no longer permitted. From this date, emails can only be sent if the sender address has the same domain as the one the email account uses. ab dem 29. Januar 2024 nicht mehr zulässig. Ab diesem Datum können E-Mails nur noch versendet werden, wenn die Absenderadresse dieselbe Domain hat wie die, die das E-Mail-Konto verwendet.

Example: You set up an email account with the email address john.doe@example.com. This address is also used for authentication on the IONOS outgoing mail server (SMTP). As the sender address, use a Gmail email address with the ending @gmail.com.

Starting January 29, 2024, you can only use return addresses that end in @example.com. Emails with a different sender, such as @gmail.com used in the example, will no longer be delivered. In this case, the IONOS outgoing mail server (SMTP) sends the following error code: Sender address is not allowed

Please note: The part of your email address before the @ sign is still freely selectable. The part of the email address after the @ sign must be the same for the sender address and the email account used.

Wenn die Absenderadresse deiner E-Mails hinter dem @-Zeichen mit der des dafür verwendeten E-Mail-Kontos übereinstimmt, musst du keine Änderungen vornehmen. Dies ist wahrscheinlich bei den meisten Benutzern der Fall.

If the domain names after the @ sign are different, immediately adjust these addresses in your email program/app, email server, or other email-enabled software.

I use an SMTP relay server, mail relay server or smarthost

An SMTP relay server (alternative name: mail relay server or smart host) is a mail server that receives emails from a sender and delivers them to third parties. An example is Microsoft Exchange. To use it, an email account (relay address) and an IONOS SPF entry must be created in the same domain.

Example: The relay address john.doe@example.com requires an SPF record at example.com.

You can find out how to create an SPF entry in the IONOAS Help Center article IONOS SPF – So that your emails are well received

The email addresses that use the SMTP relay server must belong to the same domain as the relay address stored on the mail server.

Why is this change even necessary?

Sending emails with alternative or empty email addresses may pose a security risk and may cause other email providers to reject these emails or classify them as spam. The sender address that matches the sending email account is an additional security feature, such as a license plate number.

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